This lost city belongs to one of the earliest civilizations in the world.

18th century opera in its original splendor.

This huge concrete map of Scotland was built as a thank you gift from a Polish soldier.

One of the most remote lodges in the Amazon offers rare wildlife encounters and undisturbed views of the Peruvian rainforest.

Rich red almandine gemstones are waiting inside the volcanic rock strewn across this eastern Nevada hillside.

Hidden beneath the streets of London is a secret subway that only carried mail.

Flames have been burning within this mountain for more than 2,500 years.

This museum dedicated to divination also honors a local 10th-century prophetess.

These otherworldly caverns form Earth's oldest known cave system.

In Phetchaburi, Thailand, a roadside vendor cooks his fare with 1,000 mirrors and the power of the sun.

The hidden ruins of an old hydroelectric plant reclaimed by nature.

Building owners can take out tiles for free at this repository for historic building materials.

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

Made from local Irish moss, this pie is served only in Prince Edward Island's potato museum.

From Coke II to Google Glass, this exhibit features some of the most spectacular commercial flops.

A subterranean world of tunnels links several buildings of this rare 19th-century asylum.

A beautiful ruin of a 14th-century Plantagenet castle built by a medieval mercenary.

A neutrino detector built into the largest man-made underground cavity in the world.

Underground tunnels once home to crime are now back open to the public.